Ester complexes and process of producing same



Patented Aug. 26, 1941 UNITED STATES PATENT. orr ca ESTER COMPLEXES ANDPROCESS OF PRODUCING SAME Theodore F. Bradley and William B. Johnston,

Stamford, Conn., assignors to American Cyanamld Company, New York, N.Y., a corporation of Maine No Drawing. Application April 5, 1939,

- Serial No. 266,132

21 Claims.

hydrocarbons which will be suitable for many in-' dustrial purposes.

Another object of the present invention is to provide a process by whichthe materials employed may be readily and efllciently reacted to producedirectly an alkyd-polyester mixture relatively free from undesirablepolybasic components.

These and other objects are attained by causing the fumaric acid tocombine with conjugated terpenes of the CioHm series using solubilizingand reactive alcohols to produce esters of complex organic acids whichare formed during reactions that apparently involve the unsaturation ofboth the terpenes and the iumarlc acid and are produced solely 'asesterifled derivatives by our methods as hereinafter described. We havefound that if funiaric acid ,be admixed with an alcohol and one or moreconjugated terpenes oi! the CmHiu group and the mixture be caused toreact simultaneously there results chemical .interaction of the fumaricacid, terpene and alcohol, and esters of relatively low acid number areformedin high yields without objectionable side reactions ordecompositions.

The principles and practice of our invention will be more clearlyunderstood by reference to in limitation. In each of the followingexamples the stipulated amounts of conjugated terpene, alcohol andiumaric acid are placed in a suitable reaction vasel. A suitable refluxcondenser and a water trap are preferably attached to the reactionvessel. The mixture is agitated by any suitable means during the heatingoperation and the temperature of the reactionmixture is heldcontinuously at the reflux point so that the excess of unreacted terpeneand-the water of esteriflcation are distilled together, condensed andseparated, and the separated terpene is returned to the reactionmixture.

v(Cl. 260-22) the examples given by way of illustration and not about C.and is then gradually raised to from about 180 C. to about 210 C.

The exact temperatures used in each specific case, however, areinitially subject to the boiling points of the reacting materials butgradually in crease as the water of esteriflcation'is eliminated. In allcases the reaction mixtures are best refluxed until substantially allwater evolution has ceased. Following this the excess or unreactedterpene is removed under reduced pressure and the resulting esters arerecovered for subsequent use.

Example 1 Parts by weight Fumaric acid '78 Diethylene gly v y 71 Alphaphellandrene 125 Erample 2 Parts by weight Fumaric acid 58 Triethyleneglycol '15 Alpha terp 100 This composition is heated and refluxed with.agitation for about four to seven hours at about C. A light-colored,balsam-like polyester resin is obtained having about 0.7 mol of terpenecombined per mol oi! iumaric acid. This resin is usually less viscousthan that obtained in accordance with Example 1.

Example 3 I Parts by weight Fumaric acid. I 116 Triethylene glycol.. 150A 9 p-menthadiene 150 This mixture is placed in a suitable reaction Ichamber provided with an agitator and is heated at about 175-210' C.under reflux for about four to eight hours. A light-colored, balsam-likeresin is obtained having about 0.5-0.9 mol of terpene combined per molof i'umaric acid.

Other alcohols may be substituted for those used in the above examplessuch as amyl alcohol, octadecanediol, n-butanol, glycerol, polyglycerol,

In general. the reaction mixture is heated to 55 monoaryl or alkylethers of glycerol, polyglycols or other suitable glycols. The reactivesolubilizing alcohols suitable for the practice of this invention arethose which contain non-acidic primary or secondary hydroxyl groupswhich are generally capable of esterification. Various mixtures ofalcohols may be used, especially mixtures of alcohols containingdifferent numbers of hydroxyl groups, e. g. monohydric alcohol with adihydric alcohol, a monoor dihydric alcohol with a higher polyhydricalcohol such as glycerol, etc. Monohydric alcohols alone generally yieldliquid esters of varying boiling range while the polyhydric alcoholsgenerally yield balsam-like or solid resins.

The higher polyhydric alcohols i. e. those containing three or morehydroxyl groups tend to react with the fumaric acid to yield insolublegels without eifecting sufilcient combination of the terpenes. Thistendency may be largely overcome by the use of an excess or" thealcohol, by the use of suitable catalysts and by carefully controllingthe temperature to avoid overheating, particularly in the early stage ofthe reaction. The temperature should be raised only very slowly to about170-l80 C. After the reaction has proceeded until the mixture is clear,the reaction temperature maybe raised to l802il0 C. With the highertemperatures, however, premature gelation is most likely to occur.

Characteristic of the products of this invention is the substantialabsence of esters of acids having a polybasicity greater than two,wherefore the viscosities and softening points tend to be lower than theesters prepared from the maleic-terpene adducts of the prior art. Suchdifferences may be attributable to the absence of such substantialamounts of polymeric polycarboxylic acids as have-been found tocharacterize the terpenemaleic adducts of the prior art.

By suitable regulation of the reaction conditions we may vary thecombining ratio of terpene to fumaric acid and consequently of the proportion the various esters produced within considerable limits and byvarying the solubilizing and reactive alcohols used we can produce alarge number of new and useful derivatives.

To obtain products of particularly high commercial utility, we havefound it desirable to modify some of the compositions and especially theglycerol-fumaric-terpene products in various Ways in order to obtainresins having certain valuable properties. In general our terpene resins.are more soluble in hydrocarbons than the phthalio type of alkydresins. By slight modification of our resins it is possible to obtainresins having a high degree of oil solubility, quick air dryingproperties, etc. One way of obtaining improved or soluble resins is toincorporate small amounts of fatty oil acids in the composition afterthe initial reaction of the mixture including an alcohol (e. g.glycerol), terpene and fumaric acid. After this initial reaction hastaken place, i. c. When the reaction mixture becomes clear, about ormore of fatty oil acids (calculated as triglyceride), e. g. linseed oilacids, are added to the mixture. It is especially important that thefumaric acid, alcohol and tarpene should be combined before the additionof any conjugated fatty oil acids in order to avoid reaction between thefumaric acid and the conjugated fatty oil acids before the alcohol andterpene have had suflicient time to combine. It has beenfoundadvantageous in some cases to preheat the fatty oil acids beforeadding them to the reaction mixture.

If more than 20% of fatty 011 be desired in the final product it may beadded during the latter stages of reaction in the form of either fattyoil acids or as the oil itself, as desired. Since the oil is lessexpensive than the acids it is usually preferable to add the oil itselfrather than the acids. The addition of about 20% of fatty oil acids(calculated as triglyceride) in the early stage of the reaction, asdescribed, causes the composition to become miscible with additional oilupon further reaction. Accordingly large amounts of the correspondingfatty oil or other fatty oils may be added to the composition if thetemperature be kept relatively high e. g. about 170 C.

When the resin is to be modified with fatty oil acids, additionalalcohol, equivalent to the fatty oil acids to be added, isusually addedto the original mixture of fumaric acid, terpene and alcohol.

The following exampleillustrates one method of modifying our polyesterresins as described above.

Example 4 Parts by weight Fumaric acid 58 Triethylene glycol 75 Alphaterpine e 100 Glycerol 5 to about 170 C. are added slowly to thereaction mixture. This quantity of fatty acids is equivalent to about20% of linseed oil. The reaction is continued at about 1702l0 C.forthree to four hours, yielding a balsam-like polyester resin having arelatively low acid number.

If it be desirable to incorporate more than about 20% of fatty oil orfatty oil acids, the additional amount may be added at this stage of thereaction. Aocordingly about 45 parts by weight of linseed oil may beadded to the polyester resin obtained above, the temperature of both thefatty oil and the polyester resin being maintained at about 1'70-180 C.to give a homogeneous balsamlike product particularly suitable for usein coating compositions.

Our resins may be modified with any of the fatty oils. Examples ofsuitable fatty oils are: tung, soya ,bean, perilla, grapeseed,cottonseed, olein, stearin, etc. It may be desirable to modify the resinwith drying oil, particularly if the resin is to be used in air dryingcoating compositions. For this purpose we have found that linseed oiland linseed oil fatty acids are especially suitable. The term drying oilis intended to include semidrying oils as well as the strictly dryingoils. Obviously various mixtures of fatty oils or fatty oil acids may beused. The resins produced by modification with fatty oils are usuallyquite soluble in hydrocarbon solvents. They are, therefore, particularlysuitable for use in enamels, varnishes, lacquers, etc.

Another way in which the compositions of our invention may be modifiedin order to obtain oilsoluble products is by the addition of suchsubstances as rosin acids, benzoic acid, etc., to the reaction mixture.If a conjugated compound such as rosin be used, this addition ispreferably made after all, or nearly all of the terpene has combinedwith the fumaric acid and alcohol as otherwise the modifying substancemay combine with the fumaric acid before the latter has had time tocombine with the terpene.

In operating our process, we have found it advisable, although notessential to employ sufficient excess of the terpene over the combiningequivalent for the fumaric acid so that this excess of terpene duringits volatilization may act mechanically and perhaps azeotropically toassist in the removal of the water of esterification and so promote theesterification reaction. When operating in this manner, the reactionvessel is best equipped with a suitable reflux condenser and Water traparranged so that the condensing vapors may be separated continuously,the water retained or separated and the excess terpene returned to thesystemuntil the desired degree of addition reaction and ofesterification have been attained.

In the operation of our process it is sometimes possible andadvantageous to employ inert volatile'diluents for the reaction mixture.Among materials suitable for this purpose may be mentioned benzene,toluene, xylene, ethylene dichloride or the like in place of an excessof terpene. These diluents may be removed from the product bydistillation or ifdesirable the compatible.

diluents may be left with the resin as solvents.

We have also found it possible to substitute a In orderto obtain a highratio of terpene combined with the alcohol and fumari'c acid it isdethere are a few commercial terpene distillates which containessentially a terpinene, dipentene, or terpinolene and which have aboiling point of about 1'70-185 0.

Products of this invention have been found to possess great utility. Theliquid esters derived from monohydric alcohols may be used asplasticizers for nitrocellulose and in certain cases for ethyl celluloseor other cellulose esters or ethers. These esters may be hydrogenated toprovide products suitable for the same purposes. Our

resinous polyesters'are also useful as resins or, as plasticizers forcellulose derivatives, particutics. Products of the present inventionare also useful for printing or lithographing inks, gaskets, cements oradhesives and for general coating or impregnating purposes.

Such other suitable changes and variations may be made in carryingou'tour process without departing from. the spirit and scope of ourinvention as defined in the appended claims.

We claim:

1. A process for the production of ester condensation products whichcomprises heating to reaction temperatures a mixture containing fumaricacid, a conjugated terpene of the CmHw series and a reactivesolubilizing alcohol.

2. A process for the production of ester condensation products whichcomprises heating to reaction temperatures a mixture containing.

.such as to bring about free and relatively continuous volatilizationand removal of water of sirable to employ an excess-of terpene and/or acatalyst. Suitable catalysts are included in the group of the halogens,hydrogen halides or metallic halides. Of the various catalysts whichhave been found to catalyze these reactions stannic chloride. stannicchloride-dioxanate and the sulfonic acids, e. 2., p-toluene sulfonicacid, are particularly suitable.

When dihydric alcohols are used in the practice of our in ention weprefer to em loy only the theoretical equivalent of alcohol based on theamount of fumaric acid used. although the use of lesser or greateramounts is permissible. With monohydric alcohols or those containingmore than two hydroxyl groups are used. then We usually prefer to use anexcess of the alcohol.

An excess of about 20% has been found suitable when glycerol is used.The amount of alcohol used depends somewhat on the properties desired.

. gated terpenes may be used in place of .the individual terpene.Furthermore mixtures of conjugated and non-conjugated terpenes of theCmHw j admixture and returning the terpene to the reaction.

4. A process for the production of ester condensation products whichcomprises heating a mixture containing fumaric acid, a reactivesolubilizing alcohol and.a terpene distillate, the major portion ofwhich consists of conjugated terpenes of the C1oH1c series, said heatingbeing continued 'at a temperature and for a time sufli cient to bringaboutchemical combination of the mixture.

5. A process for the production of ester condensation products whichcomprises heating to reaction temperatures a mixture containing fuma'ricacid, a reactive solubilizing alcohol, and

a conjugated terpene of the CmHm series in the t presence of a substancewhich catalyzes the reseries, e. g .,pinene may also be used. Amongthese (5.

action.

6. The process of claim 5 wherein the alcohol is a glycol.

7. A process for the production of ester condensation products whichcomprises heating to reaction temperatures a mixture containing fumarieacid, a conjugated terpene of the CmHm series and a reactivesclubilizing alcohol, continuing said until the reaction mixture hecomesclear, adding a fatty oil acid and continuing said heating until ahomogeneous product is obtained.

8, A process for the production of ester com densation products whichcomprises heating to reaction temperatures a mixture containing aconjugate-d terpene of the Ciel-11s series, a nonconjugated terpene ofthe'CmHm series, fumario acid a reactive solubilizing alcohol.

Q, The sirc itaneous reaction product of a mixtut-e contain? fumaricacid, a conjugated terpene the 310E115 series, and a glycol.

simultaneous reaction product of fumaric conjugated terpene of theCIOHiG seies -ultaneous reaction product of a containing fumaric acid,diethyiene aipha phellandrene. 2, The simultaneous reaction product of acontaining fumaric acid, triethyiene terpinene. c simultaneous reactionproduct of a containing furnaric acid, triethyiene simultaneous reactionproduct of a icing iumaric acid, an alcohol and d teroene of the Gmfizsseries modified one substance selected from the e of fatty oil acids andfatty oils. A process the production of ester con densation productswhich comprises heating: to reaction temperature a mixture contahfumaric acid, a conjugated terpene of the CmHw series and a reactivesolubilizing alcohol, continuing said heating until the reaction mixturebecomes clear, adding a fatty oil acid, continuing said heating untilthe homogeneous product is obtained, adding a fatty oil and continuingsaid heating until a homogeneous product is obtained,

16. The simultaneous reaction product of a mixture containing fumaricacid, an alcohol nd. a conjugated terpene of the (310516 series me withdrying oil fatty acids.

17. The simultan ous reaction product 0 mixture containing .tumaricacid, an alcoha conjugated t :ene the 13103116 series moi; with drying os.

18. The siinuitanecus reaction product mixture containing film? .i aconjugated tor ene of the C10 he series with a mixture of drying oil fatacids ing oils.

19. The process of claim stance which oataiyzes the chloride.

20. The process of claim 5 wherein the stance which cataiyzes thereaction is s1" chloride dioxan ate.

5 wherein the 1-" reaction is strnic sulfonic acid.

THEODORE F. WHEEL E JOHNEJ.

